#include<stdio.h>

int main(void)
{
	int n,score,i=0,failed=0;
	scanf("%d",&n);
	
	do
	{
		if(scanf("%d",&score),score<60)
		failed++;
		i++;
	}while(i<n);
	
	printf("%d",(int)100.0*failed/n);
	putchar('%');
	
	return 0;
}
